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Finding the Fourth Proportional to 421.07, 580.91 and 255.15

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Solution

The fourth proportional to 421.07, 580.91 and 255.15 is: 352.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.07 : 580.91 = 255.15 : x
  2. Step 2: Convert to fraction form
    421.07/580.91 = 255.15/x
  3. Step 3: Cross multiply
    421.07x = 580.91 × 255.15
  4. Step 4: Simplify right side
    421.07x = 148,217.91
  5. Step 5: Solve for x
    x = 148,217.91/421.07
  6. Step 6: Final answer
    x = 352.01

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.